Cerebrovascular diseases are neural function injuries caused by abnormal blood supply of regional brain. In most countries, cerebrovascular diseases, the top three causes of all deaths, can result in a brain injury in adult. Cerebrovascular disease is a major cause for endangering the health of the middle-aged and the aged people, and a major cause of death or disability of the middle-aged and the aged people in most countries.
Stroke, one of the acute cerebrovascular diseases, is the third leading cause of death in worldwide population and induces a highest disabling rate among various diseases. The cerebrovascular diseases could severely affect the life quality of the elderly, bring an enormous burden to patients' family and the society. It also tends to increase in young population.
The cerebrovascular diseases are primarily classified into two types, hemorrhagic and ischemic, of which the latter is 60-70%, and is the most common type of cerebrovascular diseases. It is important to study the pathophysiological mechanism of ischemic cerebrovascular diseases and search for drugs which function as neuroprotection.
The research of the pathophysiologic mechanism of cerebral ischemia has been one of the most focuses of the neuroscience field since 1980s, and so far theories of cerebral ischemia concerning such as energy metabolism, acid intoxication, peroxidation injury, excitatory amino acid induced toxicity injury and calcium overload have been proposed, in which the last two play an important role in ischemic neuronal injury and death. According to pathophysiologic basis of ischemic cerebrovascular diseases, drugs currently used to clinically treat cerebral ischemia mainly comprise calcium ion antagonists (nimodipine), oxygen radical scavengers (VitE, SOD), neurotrophic factors (nerve growth factor, neurotrophic factor), excitatory amino acid antagonists, antioxidants and drugs which improve late-onset neuronal injury. These drugs function via various mechanisms of action, with uncertain therapeutical effects or less specificity or with the concomitancy of severe side-effects, and thus can not meet the clinical requirements yet. There are many commercially available drugs which can be used to improve cerebral circulation, metabolism and functions, such as piracetam, flunarizine, calan, ginkgo extracts. Although they all have certain characteristics, the treatment effects thereof on cerebrovascular diseases are uncertain. Research and development of novel drugs for treating ischemic cerebrovascular diseases becomes increasingly important in the field of pharmaceutics and pharmacology.
The extracts from rabbit skin inflamed by vaccinia virus are commercially available, with the trade name of analgecine, which is manufactured by Vanworld Pharmaceutical (Rugao) Co. Ltd. Previous experiment evidence shows that crude extract of the inflammatory rabbit skins induced by inoculation of vaccinia virus can exert its pharmacological effect on analgesia. However, the active ingredients of analgecine contributing to this effect have not been reported yet. Therefore, there is a need to gain an insight into which components are involved in this effect.